The invention relates to improvements in apparatus for convoluting webs of flexible material on the cores of takeup reels, and more particularly to improvements in those parts of such winding or convoluting apparatus which serve to affix the leaders of webs to the cores of takeup reels. Still more particularly, the invention relates to improvements in apparatus which can be used with advantage in arrangements for replacing rolls of customer films in copying machines. Arrangements of such type are disclosed in commonly owned copending patent application Ser. No. 264,311 filed Nov. 28, 1988 by for "Method of and apparatus for replacing rolls of customer films in copying machines".
The copending patent application Ser. No. 264,311 discloses a photographic copying machine wherein the images of successive film frames on a long web of spliced-together exposed and developed customer films are copied while successive films are advanced stepwise from a supply reel on a first driven mandrel toward a takeup reel on a second driven mandrel. The core of the takeup reel is designed for convenient attachment of the leader of the web, and the machine is further provided with a pivotable arm which serves to grip the leader of a web in a predetermined portion of the path for the web and to transfer the properly gripped leader to a position for attachment to the core of an empty takeup reel. Each takeup reel has two flanges which are disposed at the ends of the core and one of which supports a protuberance defining with the peripheral surface of the core a gap for reception of the leader of a web which is to be convoluted onto the core. The protuberance has a sloping surface which causes the leader of the web to slide sideways toward and partially into a recess in the other flange of the takeup reel. The web is thereupon caused to move laterally toward the one flange in response to rotation of the core so that a portion of the web slides into the gap between the core and the protuberance and the next-following portions of the web are wound around the protuberance. Reference may be had also to commonly owned German Offenlegungsschrift No. 30 43 069 of Payrhammer.
A drawback of the just described takeup reel is that it is rather heavy, bulky and not sufficiently versatile. This is due to the fact that the reel must be provided with two flanges one of which carries the protuberance and the other of which is formed with the recess opposite the protuberance. The mutual spacing of the flanges is fixed so that the takeup reel is capable of storing webs having a single predetermined width. Still further, the manipulation of such reels presents problems, especially if they are surrounded by a relatively small number of convolutions, i.e., if they are not used to capacity.
Modified apparatus for attaching the leaders of webs of photographic material to the cores of takeup reels are disclosed in commonly owned German Pat. No. 33 39 618 granted to Heidrich et al.